The purpose of the current study was to examine whether oral language skills moderate the effect of Korean phonological awareness (PA) on English PA for Korean preschoolers in the initial stage of learning English as a second language. The study participants comprised 81 five- to six-year-old Korean preschoolers attending Korean-medium preschools in South Korea. The findings demonstrated that Korean PA was significantly associated with English PA. In addition, Korean receptive and expressive language skills had moderating effects on the relationship between Korean PA and English PA, respectively. This study is discussed not only in terms of cross-language PA transfer in processing two phonologically and orthographically different languages but also in light of the importance of native language skills interacting with native PA in the second-language PA development of preschool children in the initial stage of learning a second language.